Re: [PATCH v5 3/4] v4l: ti-vpe: Add VPE mem to mem driver

[Archit Taneja <archit@ti.com>]

Hi Hans,

On Friday 11 October 2013 01:16 PM, Hans Verkuil wrote:
> On 10/09/2013 04:29 PM, Archit Taneja wrote:
>> VPE is a block which consists of a single memory to memory path which can
>> perform chrominance up/down sampling, de-interlacing, scaling, and color space
>> conversion of raster or tiled YUV420 coplanar, YUV422 coplanar or YUV422
>> interleaved video formats.
>>
>> We create a mem2mem driver based primarily on the mem2mem-testdev example.
>> The de-interlacer, scaler and color space converter are all bypassed for now
>> to keep the driver simple. Chroma up/down sampler blocks are implemented, so
>> conversion beteen different YUV formats is possible.
>>
>> Each mem2mem context allocates a buffer for VPE MMR values which it will use
>> when it gets access to the VPE HW via the mem2mem queue, it also allocates
>> a VPDMA descriptor list to which configuration and data descriptors are added.
>>
>> Based on the information received via v4l2 ioctls for the source and
>> destination queues, the driver configures the values for the MMRs, and stores
>> them in the buffer. There are also some VPDMA parameters like frame start and
>> line mode which needs to be configured, these are configured by direct register
>> writes via the VPDMA helper functions.
>>
>> The driver's device_run() mem2mem op will add each descriptor based on how the
>> source and destination queues are set up for the given ctx, once the list is
>> prepared, it's submitted to VPDMA, these descriptors when parsed by VPDMA will
>> upload MMR registers, start DMA of video buffers on the various input and output
>> clients/ports.
>>
>> When the list is parsed completely(and the DMAs on all the output ports done),
>> an interrupt is generated which we use to notify that the source and destination
>> buffers are done.
>>
>> The rest of the driver is quite similar to other mem2mem drivers, we use the
>> multiplane v4l2 ioctls as the HW support coplanar formats.
>>
>> Signed-off-by: Archit Taneja <archit@ti.com>
>
> Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
>

Thanks for the Acks. Is it possible to queue these for 3.13?

Archit